require 'puppet/application'

class Puppet::Application::Resource < Puppet::Application

  attr_accessor :host, :extra_params

  def preinit
    @extra_params = []
  end

  option("--debug","-d")
  option("--verbose","-v")
  option("--edit","-e")
  option("--to_yaml","-y")

  option("--types", "-t") do |arg|
    types = []
    Puppet::Type.loadall
    Puppet::Type.eachtype do |t|
      next if t.name == :component
      types << t.name.to_s
    end
    puts types.sort
    exit
  end

  option("--param PARAM", "-p") do |arg|
    @extra_params << arg.to_sym
  end

  def help
    <<-'HELP'

puppet-resource(8) -- The resource abstraction layer shell
========

SYNOPSIS
--------
Uses the Puppet RAL to directly interact with the system.


USAGE
-----
puppet resource [-h|--help] [-d|--debug] [-v|--verbose] [-e|--edit]
  [-p|--param <parameter>] [-t|--types] [-y|--to_yaml] <type>
  [<name>] [<attribute>=<value> ...]


DESCRIPTION
-----------
This command provides simple facilities for converting current system
state into Puppet code, along with some ability to modify the current
state using Puppet's RAL.

By default, you must at least provide a type to list, in which case
puppet resource will tell you everything it knows about all resources of
that type. You can optionally specify an instance name, and puppet
resource will only describe that single instance.

If given a type, a name, and a series of <attribute>=<value> pairs,
puppet resource will modify the state of the specified resource.
Alternately, if given a type, a name, and the '--edit' flag, puppet
resource will write its output to a file, open that file in an editor,
and then apply the saved file as a Puppet transaction.


OPTIONS
-------
Note that any setting that's valid in the configuration
file is also a valid long argument. For example, 'ssldir' is a valid
setting, so you can specify '--ssldir <directory>' as an
argument.

See the configuration file documentation at
http://docs.puppetlabs.com/references/stable/configuration.html for the
full list of acceptable parameters. A commented list of all
configuration options can also be generated by running puppet with
'--genconfig'.

* --debug:
  Enable full debugging.

* --edit:
  Write the results of the query to a file, open the file in an editor,
  and read the file back in as an executable Puppet manifest.

* --host:
  When specified, connect to the resource server on the named host
  and retrieve the list of resouces of the type specified.

* --help:
  Print this help message.

* --param:
  Add more parameters to be outputted from queries.

* --types:
  List all available types.

* --verbose:
  Print extra information.

* --to_yaml:
  Output found resources in yaml format, suitable to use with Hiera and create_resources.

EXAMPLE
-------
This example uses `puppet resource` to return a Puppet configuration for
the user `luke`:

    $ puppet resource user luke
    user { 'luke':
     home => '/home/luke',
     uid => '100',
     ensure => 'present',
     comment => 'Luke Kanies,,,',
     gid => '1000',
     shell => '/bin/bash',
     groups => ['sysadmin','audio','video','puppet']
    }


AUTHOR
------
Luke Kanies


COPYRIGHT
---------
Copyright (c) 2011 Puppet Labs, LLC Licensed under the Apache 2.0 License

    HELP
  end

  def main
    type, name, params = parse_args(command_line.args)

    raise "Editing with Yaml output is not supported" if options[:edit] and options[:to_yaml]

    resources = find_or_save_resources(type, name, params)

    if options[:to_yaml]
      text = resources.
        map { |resource| resource.prune_parameters(:parameters_to_include => @extra_params).to_hierayaml }.
        join("\n")
      text.prepend("#{type.downcase}:\n")
    else
      text = resources.
        map { |resource| resource.prune_parameters(:parameters_to_include => @extra_params).to_manifest }.
        join("\n")
    end

    options[:edit] ?
      handle_editing(text) :
      (puts text)
  end

  def setup
    Puppet::Util::Log.newdestination(:console)
    set_log_level
  end

  private

  def local_key(type, name)
    [type, name].join('/')
  end

  def handle_editing(text)
    require 'tempfile'
    # Prefer the current directory, which is more likely to be secure
    # and, in the case of interactive use, accessible to the user.
    tmpfile = Tempfile.new('x2puppet', Dir.pwd)
    begin
      # sync write, so nothing buffers before we invoke the editor.
      tmpfile.sync = true
      tmpfile.puts text

      # edit the content
      system(ENV["EDITOR"] || 'vi', tmpfile.path)

      # ...and, now, pass that file to puppet to apply.  Because
      # many editors rename or replace the original file we need to
      # feed the pathname, not the file content itself, to puppet.
      system('puppet apply -v ' + tmpfile.path)
    ensure
      # The temporary file will be safely removed.
      tmpfile.close(true)
    end
  end

  def parse_args(args)
    type = args.shift or raise "You must specify the type to display"
    Puppet::Type.type(type) or raise "Could not find type #{type}"
    name = args.shift
    params = {}
    args.each do |setting|
      if setting =~ /^(\w+)=(.+)$/
        params[$1] = $2
      else
        raise "Invalid parameter setting #{setting}"
      end
    end

    [type, name, params]
  end

  def find_or_save_resources(type, name, params)
    key = local_key(type, name)

    if name
      if params.empty?
        [ Puppet::Resource.indirection.find( key ) ]
      else
        resource = Puppet::Resource.new( type, name, :parameters => params )

        # save returns [resource that was saved, transaction log from applying the resource]
        save_result = Puppet::Resource.indirection.save(resource, key)
        [ save_result.first ]
      end
    else
      if type == "file"
        raise "Listing all file instances is not supported.  Please specify a file or directory, e.g. puppet resource file /etc"
      end
      Puppet::Resource.indirection.search( key, {} )
    end
  end
end
